do you have riding exp? If not I suggest going with a 600 pre-2000 (if your looking @ sport bikes) after 2000 they started to make them much more powerful. Look for a CBR 600 (comfy, easy to ride not to tall). I would not suggest one newer than 2000 to a person new to motorcycles at all. And as far as cruisers go...you can go a little bit bigger with the motor like a 750 or so, but I wouldnt go much bigger. Cruisers arent built for speed!!! But can still hold it down. A Shadow 750 is great...you can get the shadow spirit but be careful it is a bit more touchy. AND do not forget to look into taking a MSF course...you will learn a lot about your bike and safty will riding, like avoid the dumb b*tch in the massive SUV on the phone!!! Plus you will save yourself the on bike skills test at DMV.
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Rice, Smoked snake, and Roasted pony...What have you eaten today?